You can retrieve your Order History, by inserting the email you used to purchased the product, then press the "E-Mail Order History" button. Having your Order, will allow to use the server-assisted Reinstall. If you want to know your Serial Number, insert your Order Number and Email, then press the "Submit" button on the Esellerate support site: this will enter inside your Order Page, with option to see your original Email Receipt, that contains also your Serial Number.